Rotary take-up mechanism for sewing machines



Oct. 2, 1945. 5, zoms 2,385,960

ROTARY TAKE-UP MECHANISM FOR SEWING MACHINES Filed April 11, 1944 I 3 Sheets-Sheet 1 Oct. 2, 1945. s. ZONIS 2,385,960

Romw TAKE-UP MECHANISM FOR sswme MACHINES Filed Apr il 11, 1944 s Sheets-Sheet 2 III/[III].

u. III'II/Ill 'III; 'III IIIIIII/IIIIIII/(WI/IIIII/IIII I W W Oct. 2, 1945. s. ZONIS 2,385,960

ROTARY TAKE-UP MECHANISM FOR SEWING MACHINES Filed April 11, 1944 s Sheets-Sheet :s

Patented Oct. 2, 1945 r ROTARY TAKE-UP MECHANISM FOR BIWING MACHINES Sy ney Inn Singer Bridgeport, Coma. asslgnor to The Manufacturing Company, Elisabeth, N. 1., a corporation of New Jersey Application April 11, 1044, Serial No. 530,4

1; cum. in. 112-248) This invention relates to improvementsin devices associated with rotary take-up mechanisms for sewing machines forpreventing continued abnormal winding of thread about the rotary thread-engaging take-u element or elements in the event of thread breakage.

More specifically, the present invention is in the nature of an improvement in the threadsevering device disclosed and claimed in my prior U. 8. Patent No. 2,191,736, Feb. 27, 1940. s

The primary object of this invention is to provide automatically acting means for freeing the take-up from thread abnormally engaged by the take-up elements, in the event of thread breakage during a normal stitch-forming cycle.

Other and more specific objects of the invention will be apparent from the following description and claims.

The invention consists in the thread-controlling and severing devices, combinations and arrangements of arts hereinafter described in connection with the accompanying drawings, which illustrate a preferred embodiment of the inven tion and in which:

Fig. l is a front end elevation, partly in section, of a sewing machine containing the improved thread-controlling and severing means, with the take-up cover-plate removed from the machine. Fig. 2 is an enlarged section of the rear take-up mechanism, with the take-up cover-plate applied to the machine; the section being taken on substantiall the line 2-2 of Fig. 1. Fig. 3 is an enlarged perspective view, partly in section, of the stationary thread-severing member. Fig. 4 is a fragmentary front end elevation of the take-up mechanism similar to Fig. 1 and illustrating the beginning of an abnormal engagement of the thread by the rear take-up elements in the region of the maximum slack-thread giving position of said elements. Figs. 5 to 8 inclusive 'are views similar to Fig. 4, but with the take-up progressively advanced in the succeeding figures. Fig. 9 is a detail view in front elevation of the rear take-up device and the stationary thread-severing member associated therewith, and showing thread-coils wound upon the severing member and the thread-controlling finger of the take-up. Fig. 10 is an enlarged section of the face-plate and the cover-plate associated therewith. the section being, taken on the line I 0-" of Fig. 1 and showing a portion of the take-up mechanism; Fig. 11 represents a front side elevation ofthe thread-guard which is disposed between the front and rear take-up devices, the face-plate of the I manner to impart work-advancing and return machine and the cover-plate associated therewith being shown in vertical section. Fig. 12 is a reduced front elevation of the take-up cover-plate;

The sewing machine, illustrated in the drawings, base frame includins a work-supporting bed-plate "and a hollow bracket-arm head ll. Journaled for vertical reciprocation in the bracket-arm head H is a needle-bar ll carrying at its lower end a needle 18; said needle-bar I! being endwise reciprocated vertically by any usual or suitable actuating connections with a horizontally disposed rotary actuating shaft 14.

Cooperating with the needle It, in the formation of lock-stitches, is a loop-taker lb' of the horizontal-axis rotary hook type and, as usual,

performing a plurality of rotations for each complete reciprocation of the needle l3.

The work is advanced past the stich-forming mechanism by a feed-dog is of the drop-feed type: said feed-dog ll being carried by a feed-bar ll pivotally connected, at its rearward end, to a feed-advance rocker ll actuated in any suitable movements to the feed-dog II. At. its forward end, the feed-bar H has a fork II, in which is slidably disposed a pivot-block 20 carried by a feed-lift crank-arm II. The crank-arm II is actuated in any usual or suitable manner to impart rising and falling movements to the feeddog ll. Opposed to the feed-dog "is a presserfoot 22 secured to the lower end of the usual spring-depressed presser-bar 23 which is endwise vertically movable in the bracket-arm head ll.

As more fully disclosed in the rotary take-up construction of my prior Patent No. 2,191,736

hereinbefore referred to, the actuating shaft is at the bracket-arm head end thereof carries an inner take-up disk I. The outer take-up disk of said prior construction has been cut away centrally in the present machine to provide a threadconfining ring as. The ring 25 is spaced from and secured to the disk 20 by a pair of adjacent and. preferably, radially equidistant thread-engagin studs or elements 2:. Being carried by the rotary actuating shaft ll, the take-up elements it perform one rotation for each complete reciprocation -of the needle It; said elements "rotating ina counter-clockwise direction when viewed as in Fig. 1 of the drawings.

The rear or supplemental take-up is carried by a rotary shaft 21 disposed in parallelism with and, in the present case, at substantially the level of the actuating shaft II. The shaft 21 is driven,

by suitable connections with the shaft ll, to perform two rotations for each rotation of and in the same direction as the shaft l4; said shaft 21 being joumaled adjacent its forward end in a circumferentially grooved thread-engaging studs or elements ii is an outer thread-confiningring 32 disposed. in substantially the same vertical plane as the ring 2|. The thread-engaging elements II are preferably radially equidistant and the disk ll is preferably provided centrally in its outer face .with an annular clearance-recess 38.

secured to the front end of the bracket-arm head, His a face-plate 84 provided with suitable circular openings for the disks 24 and to. Ad-

. jacent the face-plate 84, the rearward portion of the bracket-arm head II is internally provided with a shouldered segmental recess 81. Seated in said recess is the outwardly bent rim portion of one of the side flanges 38 of a reel-shaped thread-guide 39 which surrounds the hub 29 of the supplemental take-up disk in spaced relation to said hub. The other side flange 40 of said thread-guide has itsrim portion bent outwardly to extend into a shallow annular recess provided in the face-plate 34 at the inner side thereof, thereby to prevent escape of the thread between the thread-guide flange 4| and the face-plate.

Theside flanges 38 and 40 ofthe reel-shapedmember provide between them a circumferen- :ilally and axially rounded thread-guiding groove ms hub is of the at, or supplemental take-up disk has anaperture 42 extending. substantially parallel to the rotation axis of the'shaft 21.

V I'lxedly disposed in'the hub-aperture 42 is the reduced shank 43 of'a thread-controlling finger 44 which is tapered toward its outer or free end, saidfinger 44 extending outwardly through and beyond the plane of the thread-confining ring 32 The finger 44 is lengthwise 'slightlyinclined from.

the disk 1| in a direction away from the rotation I axis of said disk II. The finger 44 is also preferably disposed substantially medianly between the disk-radii of the thread-enga in elements ll, and between said elements and the axis of rotation thereof.

Spanning the space between the front and rear thread-confining rings 2| and I! is a thread-guard comprising'an arm 4| spaced from and substan-- tially parallel to the face-plate 84; said arm being integral with and extending upwardly from a base-block securedby screws, as 41, upon the facepiate 34. The front and rear edges 48 and 4! of the base-block 4| and its arm 4| are Vreversely curved; the centers of curvatureiof said edges 4| and 4| lying in substantially the'rota tion-axes of the shafts i4 and 21, respectively.

The pperedse 4| of the base-block 4| serves to limit downward movement of the portion of the x 7' thread extending between the front and rear take-up devices. while the. arm "prevents undue whipping vor that portion of the thread. i

The base-block 4| of the thread-guard is located I in the region wherein the rear thread-enga in elements ii are in that portionTof their oyclein which they are passing through maximum slackthread giving position to the position wherein said elements begin to draw up the thread. The

a,eas,aco I ner of the base-block 4| first approached by the elements II in their movement through maximum slack-thread giving position is cut away or beveled to provide a thread-deflecting face II which is inclined to the plane of the thread-confining ring 32; said face extending across and outwardly beyond the plane of the thread-confining ring 12; the outer faces of the base-block 4| and of the arm 4| being disposed outwardly of said plane.

Adjacent its thread-deflecting face 54, the baseblock 4| is provided with a recess II, in which is seated the shank I2 of a stationary thread-severing member arm 6|; said shank I! being secured to the base-block 4| by ascrew l4. The threadsevering member-arm It extends from the baseblock 4| across the take-up ring 32 at the outer side of said ring and in a direction generaliy'toward the axis of rotation of the ring. The threadsevering. arm 53 is bent to form a finger N which extends laterally from said am through the ring 32, in' close proximity to said ring and in a directionso as to be' disposed substantially normal to the plane of rotation of the take-up disk 30.

, 'Ihe finger of the stationary thread-severing member is disposed between the orbital paths of the thread-controlling finger 44 andthe take-up elements 3|; said finger 55 preferably terminating at its inner end within the face-recess II of the disk 30.

The face-portion 58 of the thread-severing member finger 55 which is proximate to the axis of rotation of the finger 44 is preferably concavely curved so asto provide clearance for said finger. As illustrated in Fig. 301' the drawings, theiside edge of the finger I! first approached by. the thread-controlling finger 44 is-beveled to form a cutting edge 61. The thread-severing member arm N is V-shaped in a'directlo'n to form a cutting-edge 58 at the side of said member last approached by the finger 44.

Removably attached to the base-block 4| and the arm 45 thereofis a flanged guard-plate 5! housing the take-up rings 2| and 32.7 The guardplate 59 is providedwith a circular opening affording access to the screws employed for securing the front take-up disk 24 for rotation with the shaft l4. A similar opening H in the rearward portion of the guard-plate ll provides clearance for the thread-controlling finger 44. Extending into the opening II is a guard-plate slot 62 affording clearance for the shank II of the thread-severing member; said slot |2 being slightly widened adjacent the opening ll. ,Pivotally attached by a screw 63 upon the outer face 7 of the rearward portion of the guard-plate II is the segmental shank 84 of a hood I! which houses the thread-controlling finger 44. A stop-screw threaded into the guard-plate I. adjacent the pivot-screw 63, isengaged by the hood-shank 64 to limit swinging movements of 'the hood 86 in opposite directions. A frictionwasher 81 is preferably associated with the pivot screw 83 to restrain th hood against free move. ment. The side flange of the hood N is partly cut away in the region of the severingmember 7 arm 53 to provide a clearance-slot BB;

The needle thread t, drawn from its supply (not shown), is threaded through the apertures of a conventional thread-guide 8| mountedpupon the bracket-arm head II. The thread t then passes downwardly through an opening (not shown) in the upper wall of the bracket-arm.

head Hand partly aroundthe thread-guide II in the groove 4i thereof to the conventional ten ion-device 69 and slack-thread controller".

tionary arm at, is bent sharply about the rim The thread then passes under the usual presser- ,bar controlled bent guide ll, upwardly at the outer side of the face-plate ll, and between the rear take-up disk It and its associated threadconfinlng ring 82 to overlie the thread-engaging elements Ii. The guide II normally directs the thread to the elements Si in substantially the plane oi the orbital path of said elements. From the rear take-up device, the thread passes torwardly between the face-plate It and the threadguard arm ll, over the thread-engaging elements It between the disk 24 and its associated ring I! of the (rent take-up device. From the front take-up device. the thread passes downwardly successively through the face-plate thread-guides I2 and II and the needle-clamp thread-guide ll to the needle II. The presser-bar controlled thread-guide II, which directs the thread to the rear take-up device, is disposed verticallybelow the rear take-up device in a vertical plane normal to the take-up disk Ill and between the axis of rotation of the disk Id and the thread-deflectins face ll of the base-block 4..

The course of the needle-thread, under normal stitching conditions, is illustrated in Fig. l

of the drawings, wherein the take-up devices are shown in approximately stitch-setting position. Throughout the normal stitch-forming cycle, the take-up elements are disposed at the under side of the thread. Should the thread break, as for example near the needle II, the rotating take-up devices tend to throw a loop a of thread in advance of the thread-engaging elements ll. and said thread-loop may assume the form illustrated' in Fig. 4 of the drawings. This abnormal condition leaves the elements II at the upper side of the thread leading from the. thread-guide II. When this occurs, the thread-loop a may in some instances be thrown by said elements 3| against the cutting-edge ll of the stationar severing fingers Bl with sufilcient violence to cause immediate severance of the thread; thereby preventing said elements from drawing further thread through the tension device It. In most cases. however, the thread-loop a will be merely drawn under the stationary thread-severing finger ll, thereby changing the normal direction of lead the thread from the guide II to the take-up.

In the movement thread-loop a from the position shown in Fig.4 to that shown in Pig. 5, a portion of the length of thread which extends to the take-up from the thread-guide it will be drawn across the stationary thread-defiectingiace so which is disposed e ternally or ring ll. As a consequence, the thread will be forced outwardly .by the inclined face is across the outer peripheral edge or rim or the ring I! at an acute angleto the plane or said ring 8!: whereby the thread or the abnormally termed and directly adlacent the leading from the guide H is v tion shown in Fig. 6 to that iii or-the thread as at an early cast upon the outer face of and by the rotating.

ring 32, in the continued as illustrated in Fi I an early stage in the abnormal windingio! the thread about the take-up elements.

In the further rotation of the rear vice, the elements page oi the thread upon the rim of the ring 82:

rotation or said ring; o! the drawings and fit partly because of the frictional dra imposed upon the thread by the tension device; and partly because of inertia oi the thread. This condition is illustrated in Fig. 8 or the drawings, wherein the thread-loop a, which extends under the staside or the take-up,

been slow that the willnot centrirugally v take-up do 3! pass beyond the blght of the thread-loop; partly by reason of someslip o! the ring caily oppositethe finger II: thread-loop a being ring 32 and the other posed between the ring 82 and the disk 3|.

In the rotation of the take-up from the shown in Fig. I o! the drawings, the thread-loop a will be carried artly around the thread-controlling finger M by the ring 32 and a second thread-loop b will be formed as an extension or the inner limb of the thread-loop a. One limb of the thread-loop b. i. e., the continuation of the inner limb of threadloop a, will then be engaged by the advance one of the take-up elements ii and will be drawn across the thread-deflecting face ll; thereby resulting in casting a second thread-limb across the rim and upon the outer face of the rin 82, as shown in Fig. 8 of the drawings.

In the rotation 01 the rear take-up from the position thereof illustrated in Fig. 7 to that shown in Fig. 8, the thread-controlling finger 44 en a es the outer limb of the thread-loop a and forms it into a third thread-loop c. In forming the thread-loop c, the tendency is to break the thread, as will be obvious from Fig. 8. However, should the thread tail to break, the thread-loop forming and casting cycles above described will be repeated by drawing upon the free end portion 0! the thread until the thread is drawn entirely oil from the take-up elements 3! and remains wound merely about the rotating finger l4 and the stationary finger II, as illustrated in Fig. 0 oi the drawin s. Should about the fingers ll and II become sufiiciently tightened, the snubbing action due to the relative movement 0! said fingers tend to break the thread. Whether or'not the thread is broken in this manner. the rotating inclined finger 44 tends to throw on the coils of thread by centrifugal action, thus leaving the take-up entirely tree 0! the thread-coils which remain hung upon the arm 53, as shown by dotted lines in Fig. 9. By pulling upon the coils hung upon the arm 53, the thread is severed by the cutting edge Ii 0! said arm '8. The slot I! 01' the thread-finger hood II and the widened portion or the guard-plate slot I! provide clearance for thethread-coils thrown of! by the finger ll. I

While diiierent conditions, such as diiierent of tension imposed upon the'thread by the tension device it or the release or the tension device. or the diilerent positions of the takeup devices when the it at a point substantially diametri one limb'ol all may result in some varia the casting oi! or the lever above described. the thread when. normally, engaged. menta II will under all tions in the time of sta e in from the take-up elements 8|."

1 Bhouldthe/speedor operation or the machine thread-eontrollingfinger R" w oi! the-thread-loop Fig. 9, the hood If en aged thereby as shown" in may be conveniently swung aside to provide aeoesstothefingerurorthemrmorremoving the loops of thread therefrom. ,The hood II is preferably provided with a plurality oi apertures II through which the presence or thread-coils upon the finger ll may be residily observed.

Having thus set forth the nature of the invention; what I claim herein is:

disposed externallyo! the limb of said loopbeine pod the coils o! thread'wound thread mm at the needle by the take-up 1-; conditions be either v I abnormal ingot theihread or will be'eomplet lyicast 08 up element in substantially the plane or rotation of said element, and means rendered eflective v upon abnormal engagement oi the thread by said take-up element for deflecting the thread laterally across the outer peripheral edge and upon the path, and thread-deflecting meansrenderod eiiective in the abnormal lead of the thread to the rotating take-up element for deflecting the thread laterally out or the orbital plane or said take-up element. I

6. In a :machine, in combination. a

thread-eng ging take-up element having an or- "bital path of rotation, means for rotating said side of said guard-ring opposite the take-up element side thereof.

2. In a sewing machine, in combination, a rotary thread-engaging take-up element, a threadconfining guard-ring rotatable with saidtake-up element, a thread-guide disposed to direct the thread to said take-up element in substantially the plane of rotation of said element, and threaddeflecting means disposed adjacent and radially externally of said. guard-ring in position for engagement by the position of the thread between said thread-guide and the take-up element under a condition of abnormal engagement oi the thread by said take-up element, said thread-deflecting means extending across the plane Of said guardring and being disposed out of eii'ective engagement by the thread during the normal stitchforming cycle.

3. In a sewing machine, in combination, a thread-engaging take-up element having an orbital path of rotation; means for rotating said take-up element,- -a thread-confining guardmember rotatable with said take-up element, a. thread-guide disposed to direct the thread to said take-up element in substantially the plane of said orbital path, the directions of lead o1 the thread tosaid element being angularly different under conditions of normal and abnormal engagement of the thread by said take-up element in the same position of said element, and means rendered effective by the angular change from normal to abnormal lead of the thread for defleeting the thread laterally across the outer peripheral edge of said guard-member.

4. In a sewing machine, in combination, a thread-engaging take-up element having an orbital path of rotation, means for rotating said take-up element, a thread-confining guard-ring carried by said take-up element for rotation therewith, a thread-guide disposed to directthe' thread to said take-up element in substantially the plane 01 said orbital path, the directions 01' lead or the thread to said element in the maximum slack-thread giving position of said takeup element being angularly diiIerent under conditions of normal and abnormal engagement of the thread by said element, and thread-deflecting means disposed externally of saidorbital path 01 the take-up element and in the path of the thread in the abnormal lead of the thread to said take-up element, said thread-deflectin means extending across the plane of said guardring at an inclination to said plane.

5. In a sewing machine, in combination, a

thread take-up element having an orbital path of rotation and about which elementthe thread may abnormally become wound, a thread-guide disposed to direct the thread to said take-up element in substantially the plane of said orbital path, the lead of the thread in said plane to said take-up element during the normal stitch-forming cycle being angularly diilerent from an abnormal lead of the thread when the thread is abnormally wound about the take-up element in the same position of said element in its orbital element, a thread-confining guard-ring rotatable with said take-up element, a thread-controlling finger having an orbital path oi rotation radially within the orbital path 01' said take-up element,

a stationary finger extending through said guard-. I 1 ring and disposed between the orbital paths of said take-up element and thread-controlling finger, a thread-guide for directing the thread to said take-up element, and thread-deflecting means disposed externally adjacent said guard-- ring in position for engagement by the thread leading from-said thread-guide to said take-up element under a condition or abnormal engagement of the thread by said take-up element.

7. In a sewing 'machine, in combination, a thread-engag ns take-up element having an orbital path of rotation, means for rotating said element, a thread-confining guard-ring rotatable with said take up element, a thread-controlling finger having an orbital path of rotation radially within the orbital path 01' said take-up element, a thread-severing member extending through said guard-ring and disposed between the orbital paths of said take-up element and thread-controlling finger, a thread-guide for directing the thread to said take-up element, and threaddefiecting means disposed externally adjacent said guard-ring and automatically rendered effective upon the thread when abnormally engaged by said take up element to deflect the thread across the outer peripheral edge of said uard-ring.

thread-engaging take-up element having an orbital path of rotation, means for rotating said element, a thread-confining guard-ring rotatable with said take-up e1ement,'a thread-controlling flnger having an orbital path of rotation radially within the orbital path of said take-up element, a thread-severing member extending through said guard-ring and disposed between the orbital paths of said take-up element and threadcontrolling finger, a thread-guide for directing the thread to said take-up element, and threaddeflecting means disposed externally adjacent said guard-ring in the region of the maximum slack-thread giving position of said take-up element, said thread-deflecting means being'disposed in the path of the thread under a con- 7 dition of abnormal engagement oi the thread by said take-up element, and said thread-deflecting means being disposed out 'of range of the thread during the normal stitch-forming cycle.

9. In a thread take-up mechanism for .sewing machines, a radially oute ithread-engaging take-up element and a radially inner threadcontrolling finger rotatable about a common axis is spaced orbital paths, said thread-controlling finger extending transversely of the plane of its orbital path and being axially inclined away from said axis in a direction toward the tree end of the finger, and .a stationary member disposed between said orbital paths in the region of the maximum slack-thread giving position of said take-up element.

for rotating said disk, a thread-engaging take-up element carried by said disk ior rotation in an orbital path, a thread-confining guard-ring carried by said take-up element in spaced relation to and for rotation with said disk, a thread-guide disposed to direct the thread to said take-up element in substantially the plane of the orbital path of said take-up element. and a thread-controlling finger carried by said disk for rotation path of said take-up element, said finger having a free end extending outwardly through said guard-ring and being axially inclined toward its tree end in a direction away from the rotation axis of said disk.

11. In a thread take-up-mechanism for sewing machines, a thread-engaging take-up element havin an orbital path-of rotation, means for rotating said element, a thread-confining guardbital path of rotation means for rotating said take-up element, a thread-confining guard-ring rotatable with said take-up element, a threadcontrolling finger rotatable with said take-up element in an orbital path radially within the orbital path of said take-up element, said threadcontrolling finger extending'through and beyond the plane of said guard-ring from the take-up element side thereof, a stationary thread-severin an orbital path radially within the orbital 1 ing member located in the region of the maximum slack-thread giving position of said take-up element. said thread-severing member comprising an arm terminating in a finger extending laterally from said arm and through said guardring carried by said take-up element, a threadguide disposed to direct the thread in substantially the plane of said orbital path for engagement by said take-up element, a thread-controlling finger rotatable with said take-up element in an orbital path radially within said guardring, said finger having a tapered free end extending through said guard-ring and being axially inclined toward its free end in a direction I away from the rotation axis of said take-up ele,

ment, a; stationary thread-severing finger extending through said guard-ring toward said disk, said thread-severing finger being disposed in the region of the maximum slack-thread giving position of said take-up element and between ring across the plane of the orbital path of said take-up element, said arm and the fingerthereoi being each provided with a cutting edge, and the finger of said arm being disposed between the orbital paths of said'take-up element and said thread-controlling finger, a hood housing the free end portion of said thread-controlling finger, said hood beingprovided with a thread-clearance slot in the region of said thread-severing member, and supporting means for said hood providing for removal of the hood from its thread-controlling finger housing position.

-l3. In a sewing machine, in combination, a rotary thread-engaging take-up element, a thread-confining guard-member associated with said take-up element and disposed to confine the thread for normal engagement by said takeup element thread-guide disposed to direct the thread to said take-up element, and means rendered effecthe orbital paths of said take-up element and tive upon abnormal engagement of the thread thread-controlling finger, and means rendered effective upon abnormal engagement of the thread by said take-up element for deflecting the thread laterally across the outer peripheral edge and upon the outer face or said guard-ring.

12. In a sewing machine, in combination, a thread-engaging take-up element having an orby said take-up element for deflecting the thread laterally across the outer peripheral edge of said guard-member and upon the side of said guard-member opposite the take-up element side 40 thereof;

SYDNEY ZONIS.

at one side of said guard-member, a f 

